1. Field of the Invention
The present invention relates to a video and audio signal output device, such as a digital TV (Television) broadcast signal receiver or a DVD (Digital Versatile Disc) recorder, for outputting video signals and audio signals to a display device such as a liquid crystal display.
2. Description of the Related Art
An AV (Audio Visual) system including a video and audio signal output device is known, which has a function to display, on a screen of a display device, information about the video and audio signal output device in the system, and a function to display, on the screen, a message for prompting a user to confirm connection of the device when the system finds no video and audio input signals by detecting presence or absence of input signals from respective input terminals (for example, refer to Japanese Laid-open patent publication Hei 4-172881). Further, Japanese Laid-open patent publication Hei 11-232853 discloses an AV system having a function to display, on a display device in the system by OSD (On Screen Display), a name of a video and audio signal output device currently sending signals to the display device. Furthermore, Japanese Laid-open patent publication Hei 3-66089 discloses such an AV system, including a television and a video device, that detects wrong connection between the television and the video device so as to emit a warning sound from a speaker of the television, and to display characters of “Wrong Connection” on a CRT (Cathode Ray Tube) of the television by OSD.
However, the technologies disclosed in these patent publications have the following problems. The technology disclosed in the above Japanese Laid-open patent publication Hei 4-172881 is not able to inform a user of a video and audio signal output device currently sending signals to the display device. Further, if the display device has multiple video signal input terminals or audio signal input terminals in use, and if no signal is input from one or ones of the input terminals, the technology disclosed therein is not able to inform the user of the one or ones of the input terminals from which no signal is input. On the other hand, the technology disclosed in Japanese Laid-open patent publication Hei 11-232853 is able to immediately inform a user of a name of a video and audio signal output device currently sending signals to the display device, if the video and audio signal output device and the display device are placed in the same room in which the user is located. However, if the video and audio signal output device and the display device are respectively placed in separate rooms, and if the user is located in the room in which the video and audio signal output device is placed, the technology disclosed therein is not able to immediately inform the user of the name of the video and audio signal output device currently sending signals to the display device. Besides, the technology disclosed in Japanese Laid-open patent publication Hei 3-66089 cannot solve such problems.